運用手持式裝置優化現地測量之效益評估

Abstract

現地測量是許多產業中重要的工作之一，涵蓋建築、土木工程、城市規劃、環境監測等多個領域，在過去，現地測量方式大多通常依賴於昂貴、笨重的專業測量儀器來進行地面測量和地理空間資訊搜集，傳統測量設備優點成熟可靠，並且通常可以提供較為精確的測量結果，不過仍有存在一些缺點，測量耗費、無法快速進行空間資訊取得，且操作以上設備皆需要專業測量知識及經驗。測量科技逐年不斷發展及進步，測量設備越做越輕巧，就連垂手可得的智慧型手機、平板等技術逐漸改變了傳統的現場測量應用方式，不過手持式測量設備必須需完全仰賴人為操作來進行數據擷取，本研究探討建立一套標準操作作業流程，透過流程可讓每位執行的測量人員所產出的成果都是很接近的，誤差值並且可在法規標準範圍內。手持式裝置在絕對精度測試上與專業RTK衛星定位儀器進行絕對精度比對驗證，比對結果手持式裝置平面誤差平均小於2公分及高程誤差平均小於1公分以內，另外驗證單一獨立點進行12小時RTK穩定性測量測試，測試結果∆E平均誤差值為2.66公分；∆N平均誤差值為1.89公分；∆N平均誤差值為4.24公分，統整以上驗證數據，手持式裝置可符合專業測量等級儀器設備標準。手持式裝置實際至現地進行測量效益驗證，並在同測區進行三組3D掃描作業，三組所產出3D模型資料導入檢核點進行精度驗證，三組3D模型成果絕對精度水平誤差平均2.3公分、垂直誤差平均3公分，相對精度平均誤差值為0.35公分，研究證明若以近距離進行3D掃描作業，手機LiDAR融合影像所產出3D模型成果，相對精度也可達到公分等級，並且在總體執行時間效益上比傳統測量設備約節省三分一以上時間。手持式裝置測量固然輕巧方便，亦可優化現地測量作業且精度可符合法規需求，但手持式裝置僅適用小範圍測量應用及有網路訊號且通透環境，若用於更大範圍或惡劣環境之測量需求並不適合，仍建議使用專業測量儀器進行，大範圍測量可建議搭配無人機作為互補，可補足地面掃描無法擷取資訊。Field surveying is a crucial task in many industries, including construction, civil en-gineering, urban planning, and environmental monitoring. In the past, field surveying methods have largely relied on expensive, bulky professional survey instruments for ground measurements and geospatial information collection. Traditional survey equipment is reliable and generally provides accurate results. However, these methods still have some drawbacks, such as high costs, slow data acquisition, and the need for specialized knowledge and experience to operate.Surveying technology has been continuously evolving, with equipment becoming in-creasingly compact. Technologies such as smartphones and tablets are gradually changing the way traditional field survey applications are conducted. However, handheld survey equipment must rely entirely on manual operation for data acquisition. This study explores the establishment of a standard operating procedure (SOP) to ensure that the results pro-duced by each surveyor are consistent and within regulatory standards.In terms of absolute accuracy testing, handheld devices were compared with profes-sional RTK satellite positioning instruments. The comparison results showed that the hor-izontal error of handheld devices averaged less than 2 cm, and the vertical error averaged less than 1 centimeter. Additionally, a single independent point underwent a 12-hour RTK stability measurement test. The test results showed an average error of 2.66 cm for ∆E, 1.89 cm for ∆N, and 4.24 cm for ∆H. These validation data demonstrate that handheld devices meet the standards of professional survey-grade equipment.For practical field measurement efficiency verification, three sets of 3D scanning op-erations were performed in the same survey area. The 3D model data from these three sets were imported for accuracy verification against control points. The results showed an av-erage horizontal error of 2.3 cm, a vertical error of 3 cm, and a relative accuracy error of 0.35 cm. The study proved that, when conducting close-range 3D scanning, the 3D mod-els produced by smartphone LiDAR integrated with images can achieve centimeter-level relative accuracy. Additionally, the overall execution time was reduced by morethan one-third compared to traditional survey equipment.While handheld devices are lightweight and convenient, optimizing field survey op-erations and meeting regulatory accuracy requirements, they are only suitable for small-scale survey applications in areas with network signals and clear environments. They are not suitable for larger areas or harsh environments. For such needs, professional survey instruments are still recommended. For large-scale surveys, it is advisable to complement handheld devices with drones, which can capture information that ground scans cannot.